JP7809206B2 - Shape memory alloy lock for connectors - Google Patents

Description

The present disclosure relates generally to connectors, and more particularly to utilizing shape memory alloys to lock an outer shell to an inner wafer of a connector.

An on-the-substrate (OTS) connector system typically includes an OTS receptacle cable assembly for electrically connecting to an OTS surface-mount technology (SMT) plug positioned on a substrate, which electrically connects to a socket on a printed circuit board assembly (PCBA). After electrically coupling the OTS receptacle cable assembly to the OTS SMT plug, a substrate underfill adhesive is used to bond the OTS connector to the substrate. The OTS receptacle cable assembly includes an inner wafer positioned within an outer shell, and a plastic clip notch that provides interference between the inner wafer and the outer shell. OTS receptacle cable assemblies are typically manufactured by a supplier and shipped to a manufacturer for assembly, with a plastic clip notch designed to hold the inner wafer to the outer shell during shipping.

One aspect of one embodiment of the present invention discloses a device comprising an electrical connector with an outer shell and an internal wafer configured to slide into a cavity in the outer shell. The device further comprises a first end of a shape memory alloy coupled to the void in the outer shell and configured to interface with an area on the internal wafer.

One aspect of one embodiment of the present invention discloses an apparatus comprising an on-board (OTS) connector with an outer shell and an internal wafer configured to slide into a cavity in the outer shell. The apparatus further comprises a plurality of surface mount technology (SMT) leads of the internal wafer configured to be mounted onto a plurality of landing pads on a printed circuit board assembly (PCBA). The apparatus further comprises a first end of a shape memory alloy coupled to the cavity in the outer shell and configured to interfere with the internal wafer and prevent movement of the internal wafer within the outer shell of the OTS connector.

Another aspect of one embodiment of the present invention discloses a method that includes applying heat to a shape memory alloy. The method further includes machining the shape memory alloy based on the dimensions and shape of the outer shell and inner wafer of the connector. The method further includes attaching a first end of the shape memory alloy to a void in the cavity of the outer shell. The method further includes inserting the inner wafer into the cavity of the outer shell to form the connector. The method further includes operating the shape memory alloy to mechanically engage with a corresponding location on the inner wafer of the connector.

The following detailed description, which is provided by way of example and is not intended to limit the disclosure to only the detailed description, is best understood in conjunction with the accompanying drawings.

FIG. 1 illustrates a front view of an exploded on-board (OTS) connector with an outer shell and an inner wafer, according to one embodiment of the present invention. FIG. 1 is a front view of an assembled on-board (OTS) connector with an outer shell and an inner wafer, according to one embodiment of the present invention. FIG. 1 is a front view of an assembled on-board (OTS) connector with a shape memory alloy hold-down clip positioned under the inner wafer before reflow, according to one embodiment of the present invention. FIG. 12 is a front view of an assembled on-board (OTS) connector with a shape memory alloy hold-down clip positioned under the inner wafer after reflow, according to one embodiment of the present invention. FIG. 10 is a close-up front view of a single shape memory alloy hold-down clip positioned under an inner wafer before reflow, according to one embodiment of the present invention. FIG. 10 is a close-up front view of a single shape memory alloy hold-down clip positioned under the inner wafer after reflow, according to one embodiment of the present invention. FIG. 10 is a close-up front view of a single shape memory alloy hold-down clip positioned within an inner wafer prior to reflow, according to one embodiment of the present invention. FIG. 10 is an enlarged cross-sectional side view of a single shape memory alloy hold-down clip positioned within an inner wafer prior to reflow, according to one embodiment of the present invention. FIG. 10 is a close-up front view of a single shape memory alloy hold-down clip positioned within an inner wafer after reflow, according to one embodiment of the present invention. FIG. 10 is an enlarged cross-sectional side view of a single shape memory alloy hold-down clip positioned within an inner wafer after reflow, according to one embodiment of the present invention. 1A-1D illustrate a process for assembling and mounting an on-board (OTS) connector with shape memory alloy hold-down clips onto a printed circuit board assembly (PCBA) according to one embodiment of the present invention.

An embodiment of the present invention provides an on-board (OTS) connector with a shape memory alloy hold-down clip for coupling the outer shell to the inner wafer. The inner wafer is positioned within the outer shell so that the surface mount technology (SMT) leads of the inner wafer contact corresponding solder paste-coated landing pads on a printed circuit board assembly (PCBA) during the attachment process. The SMT leads of the inner wafer protrude to define the mounting surface of the OTS connector. OTS connectors are often assembled by a supplier and subsequently transported and/or traded to an assembly site, which can cause the position of the outer shell relative to the inner wafer to shift. Currently, plastic hold-down clips are utilized to create an interference between the outer shell and inner wafer of the OTS connector to prevent any movement. However, if the degree of interference is too small, the inner wafer can shift within the outer shell, adversely affecting the mounting surface of the OTS connector. If the degree of interference is too great, the force required to seat the outer shell after reflow of the PCBA could potentially damage the inner wafer and/or break the plastic retaining clips.

An embodiment of the present invention provides a memory metal retainer clip for securing an outer shell to an internal wafer of an OTS connector, eliminating plastic deformation to the outer shell. The memory metal retainer clip secures the outer shell to the internal wafer at a specific distance so as not to interfere with the mounting surface of the SMT leads. A process for assembling and packaging an on-board (OTS) connector with a shape memory alloy retainer clip includes preparing an outer shell and an internal wafer for the OTS connector and selecting a memory metal, such as nitinol, that has memory material properties in the range of 90°C to 110°C. The process includes applying heat to the memory metal and machining the memory metal to a shape that provides interference (i.e., locking) between the outer shell and the internal wafer. The process includes attaching the machined memory metal to locations on the outer shell that engage with the internal wafer. After inserting the internal wafer into the outer shell to form the OTS connector, the process includes actuating the memory metal to mechanically engage with corresponding locations on the internal wafer of the formed OTS connector. The OTS connector is positioned on the surface of the PCBA, and during the reflow process, the memory metal releases (i.e., detaches) the inner wafer from the outer shell. After the PCBA with the OTS connector cools, the outer shell is pressed against the stacking surface and an encapsulant/underfill is applied to the PCBA.

Detailed embodiments of the present invention are disclosed herein with reference to the accompanying drawings. However, it should be understood that the disclosed embodiments are merely illustrative of potential embodiments of the present invention, which may take various forms. Furthermore, each of the examples given in connection with the various embodiments is also intended to be illustrative, not limiting. This description is intended to be construed merely as a representative basis for teaching those skilled in the art how to employ various aspects of the present disclosure in various ways. In the description, details of well-known features and techniques may be omitted to avoid unnecessarily obscuring the presented embodiments.

Hereinafter, for purposes of explanation, terms such as "upper," "lower," "right," "left," "vertical," "horizontal," "top," "bottom," and derivatives thereof, refer to the disclosed structures and methods as oriented in the drawings. Terms such as "above," "resting on," "atop of," "on top of," "positioned on," and "positioned atop" mean that a first element, such as a first structure, is above a second element, such as a second structure, and that there may be an intervening element, such as an interface structure, between the first and second elements. The term "directly contact" means that a first element, such as a first structure, and a second element, such as a second structure, are connected without any intermediate conductive, insulating, or semiconducting layer at the interface between the two elements. The terms "substantially" or "substantially similar" refer to instances where differences in length, height, or orientation convey no practical difference between the explicit recitation (e.g., phrases and "substantially similar" terms) and substantially similar variations. In one embodiment, substantial (and its derivatives) refers to variations in engineering or manufacturing tolerances generally accepted for similar devices, such as, for example, a 10% deviation in value or a 10° deviation in angle.

In order to avoid obscuring the presentation of embodiments of the present invention, in the following detailed description, some process steps or operations that are known in the art may be combined together for presentation and illustration purposes, and in some instances may not be described in detail. In other instances, some process steps or operations that are known in the art may not be described at all. Rather, it should be understood that the following description focuses on distinctive features or elements of various embodiments of the present invention.

FIG. 1A illustrates a front view of an exploded on-board (OTS) connector with an outer shell and an internal wafer, according to one embodiment of the present invention. The OTS connector 100 includes an outer shell 102 and an internal wafer 104 with a number of SMT leads 106 for placement on corresponding landing pads on the surface of a PCBA. The internal wafer 104 slides into a cavity in the outer shell 102 located on the back surface of the outer shell 102, the cavity being defined by a length 108 and a width 110. Prior to sliding the internal wafer 104 into the outer shell 102, a memory metal is selected to lock the internal wafer 104 within the cavity of the outer shell 102. After selecting the memory metal, heat is applied to the memory metal, and the memory metal is machined into a memory metal retainer clip according to the desired location of the internal wafer 104 within the outer shell 102 of the OTS connector 100. Memory metal retaining clips are attached to locations within the outer shell 102 that engage the internal wafer 104, and engagement of the memory metal retaining clips secures the outer shell 102 to the internal wafer 104. In this embodiment, the outer shell 102 and internal wafer 104 are associated with the OTS connector 100 and serve as an exemplary embodiment only. The invention described herein is applicable to any connector that includes at least the outer shell 102 and components that are insertable into and attachable to the outer shell 102.

FIG. 1B shows a front view of an assembled on-board (OTS) connector with an outer shell and an inner wafer, according to one embodiment of the present invention. After inserting the inner wafer 104 into the outer shell 102, heat is applied to the OTS connector 100 to activate the memory metal retaining clips into an engaged position that secures the inner wafer 104 to the outer shell 102. The position of the inner wafer 104 within the outer shell 102 is such that the SMT leads 106 of the inner wafer 104 protrude to define the mounting surface of the OTS connector 100. In the activated position, the memory metal retaining clips prevent movement of the SMT leads 106 of the inner wafer 104 relative to the outer shell 102. The memory metal retaining clips secure the outer shell 102 to the inner wafer 104 at a specific distance so as not to interfere with the mounting surface of the SMT leads 106, thereby ensuring that the SMT leads 106 contact their corresponding landing pads when placed into their desired locations on the PCBA.

2 shows a front view of an assembled on-board (OTS) connector with shape memory alloy hold-down clips positioned under the inner wafer before reflow, according to one embodiment of the present invention. In this embodiment, the OTS connector 100 includes four memory metal hold-down clips 202A, 202B, 202C, and 202D for securing the inner wafer 104 to the outer shell 102. Note that the amount of memory metal hold-down clips 202 for securing the inner wafer to the outer shell 102 depends on the design of the OTS connector 100 and the expected amount of force the OTS connector 100 will experience during shipping and/or handling processes. The memory metal hold-down clips 202A, 202B, 202C, and 202D are each in an engaged position that prevents movement of the inner wafer 104 within the outer shell 102. In the engaged position, each of memory metal hold-down clips 202A, 202B, 202C, and 202D is positioned in a respective gap 204A, 204B, 204C, and 204D in the cavity of outer shell 102, and interference between internal wafer 104 and each of memory metal hold-down clips 202A, 202B, 202C, and 202D prevents movement of internal wafer 104 within outer shell 102. When internal wafer 104 is inserted into outer shell 102, each of memory metal hold-down clips 202A, 202B, 202C, and 202D acts to mechanically engage a respective location on internal wafer 104. In the engaged position, each of the memory metal hold-down clips 202A, 202B, 202C, and 202D protrudes from a respective gap 204A, 204B, 204C, and 204D perpendicular to the movement of the inner wafer 104 within the outer shell 102. The perpendicular position of each of the memory metal hold-down clips 202A, 202B, 202C, and 202D prevents sliding movement of the inner wafer 104 within the outer shell 102 during shipping and/or handling of the OTS connector 100.

3 shows a front view of an assembled on-board (OTS) connector with shape memory alloy retainer clips positioned under the inner wafer after reflow, according to one embodiment of the present invention. In accordance with the embodiment discussed in FIG. 2, the OTS connector 100 includes four memory metal retainer clips 202A, 202B, 202C, and 202D for securing the inner wafer 104 to the outer shell 102. The memory metal retainer clips 202A, 202B, 202C, and 202D are each in a disengaged position after the reflow soldering process to the PCBA on which the OTS connector 100 is mounted. In the disengaged position, each of the memory metal retaining clips 202A, 202B, 202C, and 202D is positioned in a respective gap 204A, 204B, 204C, and 204D in the cavity of the outer shell 102, and there is no interference between the inner wafer 104 and each of the memory metal retaining clips 202A, 202B, 202C, and 202D. As a result, during the reflow soldering process and after the PCBA has cooled, the inner wafer 104 is released from the outer shell 102, and the outer shell 102 is pressed against the laminate surface of the PCBA. An encapsulant/underfill is then applied to the surface of the PCBA with the OTS connector 100.

FIG. 4A shows an enlarged front view of a single shape memory alloy hold-down clip positioned under the internal wafer before reflow, according to one embodiment of the present invention. The enlarged view of memory metal hold-down clip 202A within cavity 204A shows a single corner of outer shell 102 and internal wafer 104. An interference plane 402 represents the limit of passage between the internal wafer 104 and memory metal hold-down clip 202A attached to outer shell 102 at cavity 204A. The interference plane 402 is parallel to the sliding direction of internal wafer 104 within outer shell 102. In the engaged position before reflow, memory metal hold-down clip 202A is engaged and crosses interference plane 402, thus preventing any movement of internal wafer 104 within outer shell 102. In this embodiment, a first end of memory metal hold-down clip 202A is attached to a surface within cavity 204A, and a second end of memory metal hold-down clip 202A is not attached to any surface. The internal wafer 104 includes an area into which the memory metal retaining clip 202A can act when it crosses the interference surface 402.

FIG. 4B shows an enlarged front view of a single shape memory alloy hold-down clip positioned beneath the internal wafer after reflow, according to one embodiment of the present invention. From the enlarged view of FIG. 4A, this embodiment shows a single corner of the outer shell 102 and internal wafer 104 with the memory metal hold-down clip 202A positioned within the void 204A. As discussed previously, the interference surface 402 represents the limit of passage between the internal wafer 104 and the memory metal hold-down clip 202A attached to the outer shell 102 at the void 204A. In the disengaged position after reflow, the memory metal hold-down clip 202A does not cross the interference surface 402, thus allowing movement of the outer shell 102 from the internal wafer 104. In this embodiment, a first end of the memory metal hold-down clip 202A is attached to a surface within the void 204A, and a second end of the memory metal hold-down clip 202A is not attached to either surface. Note that the size and shape of each memory metal retaining clip depends on the size and shape of the outer shell 102 and inner wafer 104 of the OTS connector 100.

FIG. 5A shows an enlarged front view of a single shape memory alloy hold-down clip positioned within an internal wafer prior to reflow, according to one embodiment of the present invention. In this embodiment, the enlarged view of the memory metal arm 502 attached to the outer shell 102 within the cavity 504 shows a single corner of the outer shell 102 and the internal wafer 104. An interference surface 506 represents the limit of passage between the internal wafer 104 and the memory metal arm 502 attached to the outer shell 102 at the cavity 504. In the engaged position, the memory metal arm 502 is positioned across the interference surface 506 prior to reflow, thus preventing movement of the internal wafer 104 within the outer shell 102. In this embodiment, a first end of the memory metal arm 502 is attached to a surface within the cavity 504, while a second end of the memory metal arm 502 is not attached to any surface and is free to move when acted upon by applied heat. After inserting the internal wafer 104 into the outer shell 102, the memory metal arm 502 is engaged and mechanically engages with a corresponding area on the internal wafer 104. The internal wafer 104 includes a corresponding area where the memory metal arm 502 rests securely when it crosses an interference surface 506. The memory metal arm 502 is positioned within an area of the outer shell 102 and the internal wafer 104 such that the memory metal arm 502 engages with an edge of the internal wafer 104. The position of the memory metal arm 502 is such that minimal or no redesign of either the outer shell 102 or the internal wafer 104 is required to accommodate the memory metal arm 502.

5B shows an enlarged cross-sectional side view of a single shape memory alloy hold-down clip positioned within an internal wafer prior to reflow, according to one embodiment of the present invention. The enlarged cross-sectional side view of the embodiment discussed in FIG. 5A shows the outer shell 102 and internal wafer 104, with the memory metal arm 502 in an engaged position. In the engaged position, the portion of the memory metal arm 502 that intersects the interference surface 506 thus prevents the internal wafer 104 from sliding within the outer shell 102 perpendicular to the interference surface 506. Note that a memory metal arm can be positioned at each corner of the outer shell 102 to interfere with the internal wafer 104, similar to the embodiment discussed with respect to FIG. 2.

FIG. 6A shows an enlarged front view of a single shape memory alloy hold-down clip positioned within the internal wafer after reflow, according to one embodiment of the present invention. In the post-reflow disengagement position, the memory metal arm 502 is retracted and does not cross the interference surface 506, thus allowing movement of the internal wafer 104 within the outer shell 102. Movement of the outer shell 102 relative to the internal wafer 104 allows the outer shell 102 to be pressed against the stacking surface of the PCBA after reflow and cooling. FIG. 6B shows an enlarged side cross-sectional view of a single shape memory alloy hold-down clip positioned within the internal wafer after reflow, according to one embodiment of the present invention. The enlarged side cross-sectional view of the embodiment discussed in FIG. 6A shows the outer shell 102 and internal wafer 104, with the memory metal arm 502 retracted and in the disengagement position. In the disengagement position, no portion of the memory metal arm 502 crosses the interference surface 506, thus allowing the outer shell 102 to slide perpendicular to the interference surface 506, independent of the internal wafer 104.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms "a" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

The description of various embodiments of the present invention has been presented for illustrative purposes and is not intended to be exhaustive or limiting to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope of the described embodiments. The terminology used herein has been chosen to best explain the principles, practical applications, or technical improvements of the embodiments beyond those found in the art, or to enable others skilled in the art to understand the embodiments disclosed herein. Therefore, it is intended that the present invention not be limited to the exact forms and details described and illustrated, but fall within the scope of the appended claims.

Figure 7 illustrates a process for assembling and mounting an on-board (OTS) connector with a shape memory alloy hold-down clip onto a printed circuit board assembly (PCBA) in accordance with one embodiment of the present invention.

The process includes providing an outer shell and an inner wafer for the connector (702). In this embodiment, the process includes providing an outer shell and an inner wafer for the OTS connector, where the inner wafer slides into the outer shell. The outer shell containing the inner wafer forms the OTS connector, and to prevent movement of the inner wafer within the outer shell, a memory metal hold-down clip is utilized, providing interference between the outer shell and the inner wafer. The process further includes selecting a memory metal (704). Examples of memory metals (i.e., shape memory alloys) include copper-aluminum-nickel and nickel-titanium (NiTi), often referred to as nitinol. In this embodiment, nitinol is selected as the memory metal because its shape transition temperature is in the range of 90°C to 110°C. The shape transition temperature refers to the temperature at which a deformed memory metal returns to its undeformed shape when heat is applied.

The process further includes applying heat to the memory metal (706) and machining the memory metal according to the connector (708). The memory metal is heated to a shape transition temperature using one or more thermal methods, including baking, handheld heating, laser, induction, and radiant heat. In this embodiment, the memory metal (Nitinol) is heated to a value ranging from 90°C to 110°C, and the memory metal is machined to form the memory metal retainer clip. The dimensions and shape of the memory metal retainer clip machined from the memory metal are based on the dimensions and shape of the outer shell and inner wafer of the OTS connector.

The process further includes attaching (710) memory metal to locations on the outer shell that engage with the internal wafer. Attaching the memory metal to locations on the outer shell may include utilizing mounting methods including, but not limited to, heat staking, adhesives, and mechanical molding features. In one embodiment, multiple memory metal retaining clips are attached to multiple voids in the outer shell that engage multiple areas on the internal wafer, and engagement of the multiple memory metal retaining clips secures the outer shell to the internal wafer. In the disengaged position, each of the multiple memory metal retaining clips is inactive and does not cross the interface between the outer shell and the internal wafer, thus allowing movement of the internal wafer within the outer shell. A first end of the memory metal retaining clip is attached to a surface within the void, and a second end of the memory metal retaining clip is not attached to any surface and is free to move when acted upon by applied heat. The process further includes inserting (712) the internal wafer into the outer shell and engaging (714) the memory metal to the internal wafer. Each of the memory metal hold-down clips attached to the outer shell mechanically engages, by one or more means, with a corresponding location on the inner wafer to secure the inner wafer to the outer shell and form the OTS connector.

The process further includes mounting the connector onto the printed circuit board assembly (716). Before mounting the OTS connector onto the PCBA, the OTS connector is typically transported from the supplier that manufactured it to a manufacturing facility that produces the PCBA on which the OTS connector is to be mounted. Due to the action of memory metal hold-down clips, the outer shell interferes with the inner wafer, preventing any movement of the inner wafer relative to the outer shell. As a result, the mounting surface of the multiple SMT leads of the inner wafer is maintained during the transportation and handling portions of the assembly and mounting process. Mounting the OTS connector onto the PCBA includes aligning the multiple SMT leads of the inner wafer with corresponding landing pads on the PCBA, each landing pad containing solder paste for subsequently electrically and mechanically coupling the multiple SMT leads of the inner wafer. The process further includes reflow soldering the connector onto the printed circuit board assembly (718). The solder paste between each landing pad and each of the numerous SMT leads of the inner wafer reflows in a molten state to create a permanent solder joint between the landing pad and each of the numerous SMT leads of the inner wafer. During reflow soldering of the PCBA, each of the numerous memory metal hold-down clips retracts back behind the interference surface, releasing the inner wafer from the outer shell of the OTS connector.

The process further includes cooling the printed circuit board assembly (720) and pressing the outer shell against the stacking surface (722). Reflow of the PCBA causes each of the numerous memory metal retaining clips to retract back behind the interfering surface, allowing the inner wafer to move freely independent of the outer shell. However, because the numerous SMT leads of the inner wafer are soldered to the landing pads, the inner wafer remains attached to the PCBA. As a result, applying force to the outer shell causes the outer shell to be pressed against the stacking surface of the PCBA. The process further includes applying an encapsulant/underfill to the printed circuit board assembly (724). The encapsulant/underfill bonds the OTS connector to the substrate on the PCBA.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms "a" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

The descriptions of various embodiments of the present invention are presented for illustrative purposes and are not intended to be exhaustive or limiting to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein has been chosen to best explain the principles of the embodiments, practical applications, or technical improvements beyond those found in the art, or to enable others skilled in the art to understand the embodiments disclosed herein. Therefore, it is intended that the present invention not be limited to the exact forms and details described and illustrated, but fall within the scope of the appended claims.

Claims (20)

1. An apparatus comprising:
an electrical connector having an outer shell and an inner wafer configured to slide into a cavity in the outer shell;
a first end of a shape memory alloy coupled to a void in the outer shell and configured to interfere with an area on the inner wafer. The device of claim 1, wherein the shape memory alloy in the operative position is configured to prevent movement of the inner wafer within the outer shell. The device of claim 1, wherein the second end of the shape memory alloy in the operative position extends beyond the interface between the outer shell and the inner wafer. The device of claim 3, wherein the shape memory alloy in the operative position is configured to prevent movement of the inner wafer within the outer shell. The apparatus of claim 4, wherein the interference surface is parallel to the direction in which the inner wafer is configured to slide into the cavity of the outer shell. 10. The apparatus of claim 1, further comprising: one or more electrical leads of the internal wafer configured to contact one or more corresponding landing pads on a printed circuit board assembly (PCBA). The device of claim 6, wherein the shape memory alloy in the operative position is configured to prevent movement of the one or more electrical leads of the internal wafer relative to the outer shell. The device of claim 6, wherein the shape memory alloy in the operative position is configured so as not to interfere with the mounting surface of the one or more electrical leads of the internal wafer. 1. An apparatus comprising:
an on-board (OTS) connector with an outer shell and an inner wafer configured to slide into a cavity in the outer shell;
a plurality of surface mount technology (SMT) leads of the inner wafer configured to be mounted onto a plurality of landing pads on a printed circuit board assembly (PCBA);
a first end of a shape memory alloy coupled to the void in the outer shell and configured to interfere with the internal wafer to prevent movement of the internal wafer within the outer shell of the OTS connector. The device of claim 9, wherein the shape memory alloy in the operative position is configured to prevent movement of the internal wafer within the outer shell of the OTS connector. The device of claim 9, wherein the second end of the shape memory alloy in the operative position extends beyond the interface between the outer shell and the inner wafer. The device of claim 11, wherein the shape memory alloy in the operative position is configured to prevent movement of the inner wafer within the outer shell. The apparatus of claim 12, wherein the interference surface is parallel to the direction in which the inner wafer is configured to slide into the cavity of the outer shell. The device of claim 9, wherein the shape memory alloy in the operative position is configured to prevent movement of the plurality of SMT leads of the inner wafer relative to the outer shell of the OTS connector. The device of claim 9, wherein the shape memory alloy in the operative position is configured so as not to interfere with the mounting surface of the plurality of SMT leads of the internal wafer. 1. A method comprising:
applying heat to the shape memory alloy;
machining the shape memory alloy based on the dimensions and shape of the outer shell and inner wafer of the connector;
attaching a first end of the shape memory alloy to a void in the cavity of the outer shell;
inserting the inner wafer into the cavity of the outer shell to form the connector;
and causing the shape memory alloy to mechanically engage with a corresponding location on the internal wafer of the connector. placing the connector on a surface of a printed circuit board assembly (PCBA) such that one or more surface mount technology (SMT) leads of the inner wafer contact one or more corresponding landing pads on the surface of the PCBA;
reflow soldering the PCBA;
pressing the outer shell of the connector against a stacking surface of the PCBA in response to cooling the PCBA;
The method of claim 16 , further comprising: applying an underfill to the surface of the PCBA. The method of claim 17, wherein during the reflow soldering of the PCBA, solder paste electrically and mechanically couples each of the one or more SMT leads to each of the one or more landing pads on the surface. The method of claim 18, wherein cooling the PCBA causes the shape memory alloy to retract into the voids in the cavity of the outer shell. 20. The method of claim 19, wherein the applied shape of the shape memory alloy includes a second end of the shape memory alloy extending beyond the interface between the outer shell and the inner wafer.